Given below are two statements: one is labelled Assertion A and the other is labelled Reason R.

Question

G1 Physics · Accepted Answer

Nuclear force is a short-range force. A nucleon mainly interacts with only a limited number of neighbouring nucleons rather than with every nucleon in the nucleus. Therefore, for medium and heavy nuclei, total binding energy is approximately proportional to the number of nucleons A, making binding energy per nucleon nearly constant over a broad range. Thus both Assertion A and Reason R are true, and R correctly explains A. Hence option B follows.